Messages in this thread |  | | Date | Sat, 14 Sep 2002 00:02:00 -0300 | From | Werner Almesberger <> | Subject | Re: [BUG] initrd >24MB corruption (fwd) |
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Jeff Chua wrote: > Who else can help with this problem? I tried to write to Werner > Almesberger <werner.almesberger@epfl.ch> (no such email)
That one is gone. wa@almesberger.net should work for the forseeable future.
> I'm suspecting that somehow part of initrd is being corrupted during boot
The initrd is typically loaded below 16 MB. Your bzImage uncompresses after the loaded kernel, so if your kernel is, say, 3 MB and compresses to 1 MB (that's a reasonably lean 2.4.19 kernel), up to about 4.5 MB are overwritten already when getting the kernel in place. A 6 MB/2 MB kernel would happy scribble over ~8.5 MB.
See also figures 7 and 8 of http://www.almesberger.net/cv/papers/ols2k-9.ps
> ... does that mean the gzipped fs can only be <8MB? That could explain why > the ram6MB.gz worked and ram8MB.gz doesn't.
The 8 MB mapping affects mainly the maximum kernel size and shouldn't matter in this case. If you want to try anyway, you should be able to increase the mapping by pushing arch/i386/kernel/head.S:empty_zero_page down by a page, and adjusting the .org below too.
So, assuming the problem is indeed the kernel overwriting initrd, there are three things you can do to avoid this:
- use a smaller initrd (they were never meant to be quite *that* big anyway :-) - make your kernel smaller - get your boot loader to load the initrd at a higher address, or find a boot loader that does (no, I don't know which ones do, and whether they do this reliably. Section 2.5 of my booting paper (see above) explains some potential pitfalls.)
- Werner
-- _________________________________________________________________________ / Werner Almesberger, Buenos Aires, Argentina wa@almesberger.net / /_http://www.almesberger.net/____________________________________________/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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